MAL-2026-12616
Dashboard / Malicious Package / MAL-2026-12616
MAL-2026-12616
Summary: Malicious code in claims-format-date (npm)
Details: Source: amazon-inspector (776846029f9cb0fea6a6afd33178425861ef02c062754874b2a49ff078095efd) [email protected] auto-executes a binary dropper when the module is required. index.js requires./_init on load; _init.js downloads a platform-specific binary from string-split-obfuscated Cloudflare Workers hosts (oob-worker.cf102-baf.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf99-9b3.workers.dev) with a DNS TXT base64-chunk fallback through sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. The fetched bytes are written to /tmp or %TEMP% under disguised names (.cache_<uid>, dotnet_diag_<uid>.exe), chmod 0755, and detached-spawned via /bin/sh -c or cmd.exe /c start /b. Hostnames and sensitive API references are reconstructed at runtime through array joins and string concatenation (require("child_"+"process"), fs["chmod"+"Sync"]) to evade static analysis. A second parallel dropper implementation in lib/telemetry.js decodes a base64 buffer and performs the same write/chmod/exec chain under an 'analytics SDK' cover story. The package name resembles common date-formatting utilities but the shipped code implements remote payload execution on require.
Affected packages
Package
Name: claims-format-date
Purl: pkg:npm/claims-format-date
Affected ranges
Type: N/A
Events:
